1. Field of the Invention
The present invention relates to pressure vessels and, more particularly, to such vessels that are modular and can be easily fabricated into a variety of shapes and sizes.
2. Description of the Prior Art
Pressure vessels for resisting internal or external pressures are well-known and used in a variety of applications. In particular, so-called hyperbaric chambers arc widely used in the medical field, as well as in the aerospace industry as altitude chambers and space habitats. As is well-known, typically pressure vessels, including vessels forming hyperbaric chambers, are fabricated so as to have predominantly cylindrical or spherical walls so as to minimize any localized pressure-induced stresses. The problem with such shaped pressure vessels, particularly those used as pressure vessels for human occupancy (PVHO), such as hyperbaric chambers in medical applications, is that in order to make the hyperbaric chambers comfortable to patients, the structures forming the hyperbaric chambers have to be relatively large. Inherently, such vessels are heavy and difficult to transport and install. Furthermore, once installed, these prior art vessels cannot be easily modified, e.g., to change size. Clearly, a hyperbaric chamber that is rectangular in configuration is more desirable from the point of view of patient comfort and accessibility. The problem with any polygonally shaped chamber is that the individual walls of the chamber forming the polygonal shape are usually welded, or in some other manner rigidly connected, together. This invariably means that the chamber must be of a fixed size. Furthermore, as is well known to those skilled in the art, in these rigidly connected, polygonally shaped pressure vessels, the walls are subjected to bending moments that induce high bending stresses at the rigid connectionsxe2x80x94i.e., the corners where the walls interface and are connected.
It is therefore an object of the present invention to provide a pressure vessel having a cross-sectional configuration that is polygonalxe2x80x94i.e., has multiple sides.
Another object of the present invention is to provide a pressure vessel of polygonal cross-sectional configuration that can be fabricated without welding, or otherwise rigidly connecting, together the sides of the vessel forming the polygonal shape.
Still a further object of the present invention is to provide a pressure vessel that is modular in construction.
Yet a further object of the present invention is to provide a pressure vessel that can be easily transported and readily assembled at various sites.
Another object of the present invention is to provide a pressure vessel that can be readily altered as to size and shape.
The above and other objects of the present invention will become apparent from the drawings, the description given herein, and the appended claims.
In its broadest sense, the present invention provides a pressure vessel having a housing formed by at least three connected sides forming a chamber. The chamber preferably has at least one chamber opening. Each of the sides has at least two connection edges. A connector assembly flexibly, e.g., hingedly, connects a connection edge in one side to a connection edge in an adjacent side. A seal effects fluid-tight sealing between the connected sides. A closure, e.g., a bulkhead, is sealingly secured over the chamber opening when present.
In a preferred form, the present invention provides a pressure vessel having a housing formed by at least three connected sides forming a chamber, which in the case with three sides would be triangular in cross-section. The chamber has a first chamber opening and, in a preferred case, a second chamber opening. Each of the sides comprises at least one side panel. Each side panel has a web section with a first edge and a second edge, a first flange portion extending from the first edge of the web section, a second portion extending from the second edge of the web section. The first and second flange portions are substantially parallel. Each of the panels has a first end and a second end. There is a connector on each of the flange portions adjacent each of the ends of the panel, each of the connectors having a leaf projecting outwardly of the end of the panel. Each of the leaves has a first face and a second face and a bore extending through and transverse to the first and second faces, the bores in the leaves on a given end of a panel being in register. The leaves on connected ends of adjacent panels are spaced relative one another so as to interlaminate when an end of one panel is connected to the end of an adjacent panel, the bores of the interlaminated leaves being in register. A tie rod extends through the registered bores of the interlaminated leaves to hold the connected ends of the adjacent panels together. A fluid-tight seal effects sealing between adjacent sides. There is a first closure member or bulkhead sealingly secured over the first chamber opening and, in the preferred case, a second closure member or bulkhead sealingly secured over the second chamber opening. In a preferred embodiment, an access door can be provided through one of the bulkheads or through one or both of the side panels, as desired.